Fluorine containing adamantanes and bicyclo [2.2.2] octanes

ABSTRACT

Compounds of the formulas   WHEREIN N 0 TO 3 INCLUSIVE, AND Z1, Z2 and Z3 are each (CH2)n-CF3, saturated lower alkyl or hydrogen are useful as heat transfer fluids and as working fluids in Rankine cycle engines.

United States Patent 1 Tullock 1 Jan. 30, 1973 [54] FLUORINE CONTAININGChem. and Eng. News 47 15 (1969).

ADAMANTANES AND BICYCLO [2.2.2] OCTANES Primary ExaminerDaniel D.Horwitz Attorney-D. R' J. Boyd [75] Inventor: Charles William Tullock,Landenbefg, 57 ABSTRACT [73] Assignee: E. l. du Pont de Nemours and Com-Compounds of the formulas pany, Wilmington, Del. "153 31 1,", f b iii[22] Filed: Sept. 29, 1970 A [21] Appl. No.: 76,587 or z Za [52] US. Cl..260/648 F, 252/73, 424/352 [51] Int. Cl ..C07c 23/20, C070 17/22 [58]Field of Search ..260/648 F whflein n 0 to 3 inclusive and Z2 and 23 are[56] References Cited each (CH ),,-CF saturated lower alkyl or OTHERPUBLICATIONS Sohar et al., Chem. Abstracts 72, 16944h (1970).

hydrogen are useful as heat transfer fluids and as working fluids inRankine cycle engines.

7 Claims, N0 Drawings FLUORINE CONTAINING ADAMANTANES AND BICYCLO[2.2.2] OCTANES FIELD OF THE INVENTION This invention is concerned witha new class of power fluids of unusual stability and heat-exchangecapacity.

BACKGROUND Power fluids for use in closed Rankine-cycle turbine enginesrequire exceptional stability to heat in the presence of metals used inengine construction. If a single stage turbine engine is used, they mustfurther be characterized by high vapor density so that the speed of theturbine is not excessive, and by a moderately high molecular weight(e.g., 150).

SUMMARY OF THE INVENTION There have now been discovered the bridgehead(fluoroalkyl-substituted), multicyclic, saturated hydrocarbonscharacterized by having a molecular weight above 200, a boiling point inthe range of 170300 C. and a critical temperature at least 175C. abovethe boiling point. These compounds are stable at 300C. in the presenceof selected metals for a time period in excess of 90 days. The compoundsare the adamantanes and bicyclo[2.2.2]octanes, in which at least onebridgehead carbon carries a substituent (CH ),,CF in which n is 0, l, 2,or 3; the remaining bridgeheads carry (CH ),,-CF saturated lower alkylof up to four carbon atoms or hydrogen; and all non-bridgehead positionscarry hydrogen. These compounds have the formulas:

I in which each of Z, Z, and Z is --(CI-I,),,CF5, saturated lower alkylor hydrogen, n being defined as above.

In these compounds it is important that the non bridgehead ringpositions be CH groups. Any substitution at these positions oftendecreases the heat and chemical stability of the compound. It isparticularly important to avoid fluorine substituents at nonbridgeheadring positions.

Preferred compounds of Formulas l and 11 are those in which n is or 1,particularly those in which n is 0, and Z, Z, and Z is hydrogen ormethyl.

The cyclic skeletons of the compounds of this invention are composedentirely of six-membered aliphatic carbon rings. All the ring carbonsare either bridgehead carbons or CH groups. The term bridgehead carbondefines a carbon atom connected directly to three other carbon atoms(i.e., CH groups) and having only its single remaining bond available tocarry hydrogen or a substituent as defined above.

The selected metals against which the compounds of this invention arestable in excess of 90 days at 300C. include copper, 1020 coldrolledsteel, 304 stainless steel, and aluminum. The tests are carriedout in the absence of air and moisture. A compound is rated stable ifthe maximum result of the heat treatment is a color change or depositionof a thin coating on the surface of the metal and there is no grosschemical breakdown of the compound.

Because of their unusual stability to heat in the presence of metals,the compounds of this invention are all useful as heat-exchange fluidsfor all equipment in which fluid heat-exchange is carried out as well aspower fluids in closed Rankine-cycle turbine engines.

A closed heat-exchange or power system is advantageous for employing thecompounds of this invention since the vapors of the fluids are toxic torats in acute inhalation toxicity experiments and are presumably toxicto humans. Appropriate care must be exercised to prevent escape of thevapors, particularly at high temperatures.

A process suitable for making the compounds of the invention is that ofSmith, US. Pat. No. 2,859,245. In this process an adamantane orbicyclo[2.2.2]octane having on at least one of its bridgehead positionsa carboxy, or a carboxyalkyl group is treated with sulfur tetrafluorideto convert the COOH group to a CF;, group. The chemistry of the processmay be represented schematically by the equation:

The hydrogen fluoride formed in this reaction apparently catalyzes thecontinuation of the process since the reaction does not proceed in thepresence of a strong absorbent for hydrogen fluoride such as sodiumfluoride. On the other hand, addition of hydrogen fluoride beyond theamount formed is not necessary since this favors fluoride substitutionon other bridgehead carbon atoms to yield byproducts of poor thermalstability. It is for this reason that it is advisable to carry out theprocess in the absence of moisture since water reacts readily with SF toproduce HF.

No added reaction medium is required for carrying out the process ofthis invention. However, as shown in the examples, the reaction may becarried out in the presence of a liquid which is inert to the reactantsand products, s'uch as l,2-difluorotetrachloroethane.

The process may be carried out at temperatures in the range from 0-200C.and preferably in the range from SO -C. Pressure is not a criticalvariable in the process and pressures above and below atmosphericpressure may be used.

The molar proportions of sulfur tetrafluoride to carboxylic acid, whichmay be brought together to bring about the reaction of this inventionare not limited in any way. Any proportion of the two reactants willproduce at least some of the trifluoromethyl product. For practicalpurposes it is easiest to isolate the desired product when the molarproportions of SP to COOH are within the range from 10:1 to 1:1 and bestyields are obtained in the range from 4:1 to 2:1.

' The products are isolated by known means such as by distillation,chromatography, and the like. Isolation of a pure product isparticularly desirable since impurities can decrease the thermalstability of the product.

Adamantane' carboxylic acids are well known. Thusadamantane-l-carboxylic acid is described by H. Stetter and E. Rauscher,Chem. Ber., 93 1 161 (1960);

'mantane-7-carboxylic acid have been disclosed by H.

Koch and .1. Franken, Chem. Ber. 96, 213-9 (1963). Likewise,bicyclo[2.2.2]octane-l-carboxylic acid has been disclosed by C. Grob, M.Ohla, E. Renk and A. Weiss, Helv. Chim. Acta 41, 1191-7 (1958) andbicyclo[2.2.2]octane-1,4-dicarboxylic acid by J. C.

Kauer, R. E. Benson & G. W. Parshall, J. Org. Chem- 30, 1431-6 (1965).The synthesisof bicyclo[2.2.2]octane-l-carboxylic acid with variousalkyl substituents substituted in the 4 position has been described byH.

r). Holtz and L. M. Stock, .1. Am. Chem. Soc. 86,

5183-8 (1964), and by Whitney et al., J. Medicinal Chemistry 13, 254(1970).

Carboxylic-acid groups can be inserted in vacant bridgehead positions ofadamantanes or substituted adamantanes by carbonylation as shown inExample 14 of the appended examples.

Homologues of adamantane carboxylic acids can be made by application ofthe Arndt-Eistert reaction to the carboxylic acid as shown by H.Stetter, M. Schwartz and A. A; Hirschhorn, Chem. Ber. 92, 162935 (,1959)who employed this reaction to make adamantane-lacetic acid. Cfo, Fieserand FiesenAdvanced Organic Chemistry, Reinhold Publishing Corp., NewYork, N. Y., 1961 pp. 386-388.

C'arboxylic acids can also be made from halides such as chlorides,bromides or iodides by forming a Grignard reagent, reacting the Grignardreagent with carbon dioxide and hydrolyzing the product. Thusl-adamantyl acetic acid has been made from l-(bromomethyl)-adamantane bythis route by N. F. Stepanov and V. F. Baklos, Zh. Obsch-Khimf 34,579-84 (1964). H, Stetter and P. Goebel have shown thatl-bromo-adamantane can be reacted with ethylene in the presence ofaluminum bromide to form l-ada'mantyle thylenebromide. The lattercompound can be converted to the 3-substituted propionic acid asdescribed above.

K. Bott, Angew, Chem. 77,967 (1965) has described yet another .route' toadamantane substituted at a bridgehead with an acetic acid group.

The Arndt-Eistert reaction can likewise be used to prepare higherhomologues of bicyclo[2.2.2]octane monoand dicarboxylic acid.

In the examples which follow, parts and percentages are by weight unlessotherwise specified. These examples are intended to illustrate theinvention and are not intended to be limiting.

EXAMPLE 1 1-(Trifluoromethyl)adamantane l-Adamantanecarboxylic acid (34g; 0.189 mole) and sulfur tetrafluoride (63 g; 0.583 mole) were heatedin a 235-ml Hastelloy pressure reactor, free of air, at 50C for 1 hour,75C for one hour, 100C for 1 hour, and at 125C for 1 hour. The crudeproduct (37.4 g). was washed with 5% NaOH solution to remove hydrogenfluoride and any adamantanecarboxylic acid fluoride, taken up in1,1,2-trifluorotrichloroethane,

washed with water, the solution dried over MgSO, and the productdistilled through a 6-inch spinning band column. There was obtained 29.5g of a colorless,

somewhat viscous liquid with a camphor-like odor, bp

-81C/20 mrn. Vapor phase chromotographic analysis indicated the productwas 93.8 percent 1- (trifluoromethyl)adamantane, and that 5.8 percent ofa minor component was present. Fluorine nuclear magnetic resonancespectra revealed as major peaks a large singlet in the CF region for theproduct, with a much smaller doublet in the CF;; region; the areas ofthe two peaks were present in about a 15:1 ratio. The impurity wasidentified as 3-fluoro-l-(triflu0romethyl)adamantane. The singlebridgehead fluorine splits the CE, fluorinespectrum into a doublet.

' A pure sample of l-(trifluoromethyl)adamantane was recovered by avapor phase chromatographic separation. Anal. Calcd. for C,,H, F C,64.7; H, 7.35; F, 27.9

Found: C, 64.6; H, 7.30; F, 28.5. The boiling point of the pure productat atmospheric pressure as obtained by differential thermal analysis(DTA) was 200C; the pure compound melted at 8C. The critical temperaturewas found to be 419C.

Pure l-(trifluoromethyl)adamantane exhibited exceptional heat stability.Test portions of thisv material were heated in sealed evacuated Pyrextubes at 350C in contact with strips of copper, 1020-ordinary coldrolledsteel and 304-stainless steel for l 13 days without noticeable change inthe liquid. The copper and 304 metal coupons became dulled during thisperiod; the 1020 steel developed a firm steeLblue coat on the metalsurface.

A similar series of heat stability tests of 1-(trifluoromethyl)adamantane with a control tube as well as tubescontaining strips of copper, aluminum, 1020-ordinary steel and304-stainless steel were run at 300C for 108 days. No change either inthe fluid or the metal surface was noted in any of the five tubes,except for a slight darkening of the 1020-ordinary steel surface.

This combination of exceptional heat stability not only alone but incontact with metals, and a spread of 219C between the criticaltemperature and boiling point in combination with a boiling point of200C and a molecular weight of 204 make the material an excellentworking fluid for an air-cooled turbine operating in a closed Rankinecycle.

EXAMPLE 2 l-Adamantanecarboxylic acid g; 0.56 mole) was placed in aHastelloy pressure reactor which was closed and warmed at 5060C for 1hour under a vacuum below 1 mm to remove traces of moisture from theacid and the reactor. .The reactor was then closed while still underhigh vacuum, cooled to 7 8C and sulfur tetrafluoride (180 g; 1.67 mole)was added. The reactants were then warmed with gentle rocking at 50C for2 hours and at 75C for 8 hours. The crude product was warmed withstirring with a solution of 50 g of KOH dissolved in 500 ml of water at7075C for 6 hours. This removed the small amounts of hydrogen fluoridepresent and the slowly hydrolyzable l-adamantanecarboxylic acidfluoride. The product was next dissolved in an equal volume of 1,1,2-

trifluorotrichloroethane. This solution was washed with water, driedbriefly and concentrated. The product remaining was next stirred with500 ml of concentrated H SO at room temperature for 16 hours to removethe bridgehead-fluorinated impurities. The product was separated fromthe heavier light brown colored sulfuric acid layer and dissolved in1,1,2- trifluorotrichloroethane. The resulting solution was washed inwater, dried briefly and distilled through a 6- inch spinning bandcolumn. There was obtained 88.2 g

with stirring with a solution of 40 g of KOH in 300 cc of water at 5068Cfor 2.25 hours, to remove small amounts of hydrogen fluoride andadamantanecarboxylic acid fluoride. The product was next taken up in anequal volume of l,l,2-trifluorotrichloroethane, dried briefly anddistilled through a 6-inch spinning band column; 30.7 g of material, bp7577C/l4 mm was recovered. Vapor phase chromatographic analysisindicated the product was 30% 1 ,3- di(trifluoromethyl)adamantane and60.8% 1,3- di(trifluoromethyl)--fluoroadamantane. A portion of thedistilled product was subjected to vapor phase chromatographicseparation. There was recovered 1.41 g (amounting to 41 percent) of 1,3-di(trifluoromethyl)adamantane (A) and 2.04 g (amounting to 59 percent)of l,3-di(trifluoromethyl)- 5-fluoroadamantane (B).

Fluorine nmr of (A) showed the presence of a single large fluorine peakin the CF, region which had no fine TABLE 1 [Preparation of1-(trifluoromethyl) adamantane] Product purity Hastelloy based reactor011 VPC size analysis Conver- Example Reactants Moles (m1.) Reactionconditions (percent) sion 1-Ad-C02H 0.139 235 C. for 8 hours withrocking, then stood at 82 3 SF, 0. 41s 25 0. for an additional 8 hours.4 l-Ad-COgH 3.5g; 035 50 C. for 8 hours 85 67 O 5 3 3 333% 235 {22 81i8? 3 1335213131131 :jjj} 17 l-Ad-COJI 0.139 235 50 C. for 1 hour o 0,4175 C. for 1 hour. M 76 100 C. for 4 hours 7 Hui-(.0 11 235 125 for 8hours an 53 F .'..7 8 l-Ad-UOdl g 800 125 (F. for 8 hours 72 1g 4 l .c011 0.13!) 120' C. for 8 hours 00 60 J SF, 0. 416

m.l of Freon112 Vapor phase chromatography.*1,2-difluor0tetrachloroethane.

EXAMPLE 10 l,3-Di(trifluoromethyl)adamantane Adamantane-l,3-dicarboxylicacid (20 g; 0.089 mole) and SF, g; 0.555 mole) were heated in a 235- mlHastelloy pressure reactor, free of air, at C for 1 hour, C for 1 hour,and 125C for 8 hours. The crude product recovered was first stirred withexcess 15% KOH solution at 6065C for 20 minutes. Infrared analysisindicated by absorption at 5.45 p. the probable presence of carboxylicacid fluoride, so the product was warmed again with stirring with asolution of 20 g of KOH in 200 m1 of water at 59-69C for 2 hours. Theproduct, now free of the 5.45 p. impurity, was distilled through a6-inch spinning band column; there was recovered 8.67 g of 1,3-di(trifluoromethyl)adamantane in the form of a colorless liquid, bp83.0-83.8C/13 mm. Vapor phase chromatographic analysis indicated theproduct was 90-92% pure.

EXAMPLE 1 l l,3-Di(trifluoromethyl)adamantaneAdamantane-l,3-dicarboxylic acid (35.0 g; 0.156 mole) and sulfurtetrafluoride g; 0.972 mole) were heated with rocking in a Hastelloypressure reactor, free of air, at 75C for 1 hour, 100C for 1 hour, and Cfor 8 hours. The crude product was warmed structures even on highresolution. Vapor phase chromatographic analysis indicated the productwas 98.7% pure.

Anal. Calcd. for C H F C, 52.9; H, 5.2: F, 41.9

Found: C, 53.1; H, 5.0; F, 42.1 The compound boiled at 208C at ordinarypressure (DTA its critical temperature was 409C.

Fluorine nmr of (B) showed the presence of a large doublet in the CFregion, and a second peak which had no fine structures even under highresolution; the two peaks had areas which approximated a 6:1 ratio.Vapor phase chromatographic analysis indicated the compound was 97.4percent pure.

Anal. Calcd. for C, H F C, 49.6; H, 4.5; F, 45.9

Found: C, 49.7; H, 4.1; F, 46.0.

Another portion (10 g) of the original distillate containing 30%l,3-di(trifluoromethyl)adamantane and 50 ml of 98 percent sulfuric acidwere stirred at room temperature for 18.5 hours. The acid insolublefraction was taken up in 1,1,2-trifluorotrichloroethane and distilledthrough a 6-inch spinning band column; 2.38 g of 1,3-di(trifluoromethyl)-adamantane, bp 89.5C/ 16.5 mm was recovered.

Heat stability studies with l,3-di(trifluoromethyl)- adamantane at 350Cin sealed evacuated Pyrex glass tubes in contact with selected metalsindicate the fluid is exceptionally heat stable. After 97 days underthese conditions, 304-stainless steel was unaffected, while lVUv-r e...

the surface of the copper coupon was only moderately dulled. The1020-ordinary steel had a thin blue-violet colored coat. in no case wasthe fluid itself noticeably changed.

EXAMPLE 12 1-(2,2,2-Trifluoroethy1)adamantane LAdamantaneacetic acid (25g; 0.129 mole) and sulfur tetrafluoride (42 g; 0.389 mole) were heatedwith rocking in a 235-ml Hastelloy pressure reactor, free of air, at 75Cfor 1 hour, 100C for 1 hour, and 125C for 8 hours. The crude product(30.5 g) was washed with percent aqueous sodium hydroxide, but this didnot remove all the organic acid fluoride present. The product was nextstirred at 5060C for 2 hours with excess NaOH solution. The product wastaken up in an equal volume of 1,1,2- trifluorotrichloroethane, thesolution washed with water and dried over MgSO Distillation yielded thethree following cuts:

Vapor Phase Chromatographic Cut No. BP "Clmm Weight Analysis 2.34 g (C)63.8% (D) 34.0% (C) 50.3% (D) 47.5% (C) 25.8% (D) 70.3%

Cuts 1, 2, and 3 were composited and subjected to a vapor phasechromatographic separation. The two major components present wereseparated and in about equal amounts. Compound (C) was 1-(2,2,2-trifluoroethyl)adamantane.

Anal. Calcd. for C ll F z C, 66.1; H, 7.8; F, 26.1

Found: C, 65.9; H, 7.9; F, 26.2.

Fluorine nmr of (C) showed the presence of one large fluorine peak inthe CF region which under high resolution was a triplet. This wasevidence for the CH,CF grouping. The compound had a boiling point of217C (DTA) at ordinary pressure, and a critical temperature above 430C.No visible change in the fluid resulted on heating it-to 430C. Thecompound was heat-stable at 300C for 91 days in contact with1020-ordinary steelin a sealed evacuated Pyrex tube; during this test adark coat developed on the glass where liquid covered, the fluiddeveloped a light yellow color and the surface of the metal coupondeveloped a dark coat. These tests showed that the compound is stable at300C for extended periods. Compound (D) wasl-(2,2,2-trifluoroethyl)-3-fluoroadamantane.

Anal. Calcd. for C,,H, -,F C, 61.0; H, 6.8; F, 32.2

Found: C, 61.2; H, 6.9; F, 31.5.

Fluorine nmr of (D) showed two different fluorine peaks in about 3:1ratio. The larger peak under high resolution was a triplet and thesmaller peak was a broad band with no fine structures, which would beexpected for a fluorine on a tertiary carbon. The compound distilled at233C at ordinary pressure (DTA) and underwent excessive degradation whenheated to 260C in an effort to obtain the compounds criticaltemperature.

EXAMPLE 13 1-(Trifluoromethyl)-3,5-dimethyladamantane Crudel,3-dimethyladamantane-S-carboxylic acid (11 g; 0.053 mole), (preparedby reacting 1,3- dimethyladamantane with carbon monoxide in sulfuricacid) and 25 g (0.232 mole) of SF, were heated in a 235-ml Hastelloypressure reactor at C for 1 hour and 125C for 3 hours. The 9.9 g ofcrude product recovered was warmed with stirring with a solution of 15 gof KOH in 100 ml of H 0 at 6575C for 2 hours. The product was extractedwith 1,1,2 trifluorotrichloroethane. Distillation yielded 3.03 g of1-(trifluoromethyl)-3,S-dimethyladamantane, bp 82C/10 mm; F nmr was inagreement with the proposed structure. Vapor phase chromatographicanalysis suggested the compound was 88.2 percent pure. A pure sample wasrecovered by vapor phase chromatography. The compound boiled at 210C (byDTA analysis). lts critical temperature was 419C. Anal. Calcd. for C H FC, 67.2; H, 8.2; F, 24.6

Found: C, 67.3; H, 8.0; F, 25.1.

EXAMPLE 14 1 ,3-Di(trifluoromethyl)5 ,7-dimethyladamantane Part A Amixture of 50 g (0.305 mole) of 1,3-dimethyladamantane and 200 ml ofconcentrated sulfuric acid was heated at 150C for 4 hours under apressure of 500 atmospheres of carbon monoxide. The product was mixedwith ice and water. After extracting with 500 ml of warm carbontetrachloride, the remaining solid was dissolved in excess 15 percentaqueous sodium carbonate. This solution was acidified to precipitate 37g of crude 1,3-dimethyl-5,7-adamantanecarboxylic acid. This was purifiedby extracting twice with 500 ml of boiling diethyl ether andconcentrating the ether extract to obtain 23 g of1,3-dimethyl-5,7-adamantanedicarboxylic acid. I Anal. Calcd. for C H OC, 66.7; H, 7.9; NE. 126

Found: C, 66.6; H, 8.0; NE. 125

Part B i A mixture of 25 g (0.099) mole of 1,3-dimethyl-5,7-adamantanedicarboxylic acid and 60 g (0.556 mole) of SF was heated at125C for 6 hours in a Hastelloy pressure reactor. The crude product wasfirst heated with a solution of 30 g of R011 in 250 ml of water at 6065Cfor 2 hours. The remaining insoluble product was extracted with1,1,2-trifluorotrichloroethane andthe extract distilled through a 4-inchVigreaux column to obtain 20.3 g of1,3-di(trif1uoromethyl)-5,7-dimethyladamantane, mp 52-57C, bp 92C at 11mm and 218C at atmospheric pressure (DTA). Fluorine nmr showed a singlefluorine peak in the CF region with no fine structure. Vapor phasechromatographic analysis indicated the product was 92.8 percent pure.Anal. Calcd. for C H F C, 56.0; H,6.0; F, 38.0

Found: C, 56.1; H, 6.1;F, 37.5.

EXAMPLE 15 1,4-Di(trifluoromethyl)bicyclo[g2.2.2]octane1,4-Bicyclo[2.2.2]octanedicarboxylic acid (31 g; 0.157 mole) and sulfurtetrafluoride g; 0.787 mole) were heated with rocking in 235-mlHastelloy pressure reactor, free of air, at 75C for 1 hour, C for 1hour, and C for 8 hours. The crude product (29.6 g) was washed well witha solution of 20 g of KOH in ml of water, taken up in an equal volume of1,1,2- trifluorotrichloroethane, this solution washed with water, driedover MgSO and distilled through a short 4-inch modified Vigreaux column.The material (17.1 g), which was a solid at room temperature, boiled at167169C. A vapor phase chromatographic analysis indicated the productwas 98.4 percent pure, it was subjected to a vapor phase chromatographicseparation and the pure l,4-di(trifluoromethyl)bicyclo[10ctane asrecovered was analyzed.

Anal. Calcd. for C H F C, 48.7; H, 4.9; F, 46.3

Found: C, 49.0; H, 5.1; F, 45.3.

The pure compound distilled at 171C at ordinary pressure (DTA); itmelted at 5253C. The fluorine nmr showed a single large peak with nofine structure in the CF;, region. The material had a criticaltemperature of 360C.

Heat-stability tests with the material run at 300C in sealed evacuatedtubes in contact with metals indicate this is an unusually heat-stablematerial. After 90 days at 300C there was a light dulling of the metalsurfaces of copper, aluminum, 1020-ordinary steel and 304- stainlesssteel. The fluid itself was not noticeably changed in these or in acontrol experiment.

When the carboxylic acids listed in Table 11 below are substituted forl-adamantanecarboxylic acid in the procedure of Example 2 andproportional molar quantities of sulfur tetrafluoride are employed, theindicated trifluoromethyl derivatives are obtained.

TABLE II Item Carboxylic Acid Trifluoromethyl Productl-Methyl-B-adamantanel-Trifluoromethyl-3-methyladacarboxylic acidmantane1,3,5-Trimethyl-7-adal-Trifluoromethyl-3,S,7-trimantanecarboxylic acidmethyladamantane 3 l.3,5,7-Adamantanel ,3,S,7-Tetra(trifluoromethyl)- 4tetracarboxylic acid adamantaneBicyclo[2.2.2]octanel-(Trifluoromethyl)bicyclowherein ri is 0 to 3inclusive, and

Z, Z and Z are each (CH ),,CF saturated lower alkyl or hydrogen.

. l-Trifluoromethyladamantane. l,3-Di(trifluoromethyl)adamantane.

. l-(2,2,2-Trifluoroethyl)adamantane.

. l-(Trifluoromethyl)-3,S-dimethyladamantane.

. l,3-Di(trifluoromethyl)-5,7-dimethyladamantane.l,4-Di(trifluoromethyl)bicyclo[g2.2.2]octane.

1. A compound having the formula
 2. 1-Trifluoromethyladamantane. 3.1,3-Di(trifluoromethyl)adamantane. 4.1-(2,2,2-Trifluoroethyl)adamantane. 5.1-(Trifluoromethyl)-3,5-dimethyladamantane. 6.1,3-Di(trifluoromethyl)-5,7-dimethyladamantane.